diff --git a/src/main/java/org/gcube/portal/oidc/lr62/OpenIdConnectAutoLogin.java b/src/main/java/org/gcube/portal/oidc/lr62/OpenIdConnectAutoLogin.java
index 93153a2..bea26ba 100644
--- a/src/main/java/org/gcube/portal/oidc/lr62/OpenIdConnectAutoLogin.java
+++ b/src/main/java/org/gcube/portal/oidc/lr62/OpenIdConnectAutoLogin.java
@@ -1,10 +1,14 @@
 package org.gcube.portal.oidc.lr62;
 
+import java.awt.image.BufferedImage;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
 import java.util.Arrays;
 import java.util.Calendar;
 import java.util.Locale;
 import java.util.UUID;
 
+import javax.imageio.ImageIO;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
@@ -29,6 +33,9 @@ public class OpenIdConnectAutoLogin extends BaseAutoLogin {
 
     private static final Log log = LogFactoryUtil.getLog(OpenIdConnectAutoLogin.class);
 
+    private static boolean ASSURE_AVATAR_FORMAT = true;
+    private static String DEFAULT_AVATAR_FORMAT = "png";
+
     @Override
     public String[] doLogin(HttpServletRequest request, HttpServletResponse response) throws Exception {
         if (log.isTraceEnabled() && request.getSession(false) != null) {
@@ -119,7 +126,23 @@ public class OpenIdConnectAutoLogin extends BaseAutoLogin {
 
             try {
                 byte[] userAvatar = OpenIdConnectRESTHelper.getUserAvatar(configuration.getAvatarURL(), token);
-                if (userAvatar != null) {
+                if (userAvatar != null && userAvatar.length > 0) {
+                    if (ASSURE_AVATAR_FORMAT) {
+                        log.debug("Assuring avatar image format as: " + DEFAULT_AVATAR_FORMAT);
+                        log.debug("Reading image stream with length: " + userAvatar.length);
+                        BufferedImage bi = ImageIO.read(new ByteArrayInputStream(userAvatar));
+                        if (bi != null) {
+                            ByteArrayOutputStream baos = new ByteArrayOutputStream();
+                            log.debug("Converting avatar stream image format to: " + DEFAULT_AVATAR_FORMAT);
+                            ImageIO.write(bi, DEFAULT_AVATAR_FORMAT, baos);
+                            baos.flush();
+                            baos.close();
+                            log.debug("Reading converted image from the BAOS");
+                            userAvatar = baos.toByteArray();
+                        } else {
+                            log.warn("Buffered image read is null!");
+                        }
+                    }
                     log.debug("Saving the retrieved avatar as user's portrait");
                     UserLocalServiceUtil.updatePortrait(user.getUserId(), userAvatar);
                 } else {
diff --git a/src/test/java/ImageTest.java b/src/test/java/ImageTest.java
new file mode 100644
index 0000000..a99afc9
--- /dev/null
+++ b/src/test/java/ImageTest.java
@@ -0,0 +1,18 @@
+
+
+import java.awt.image.BufferedImage;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+
+import javax.imageio.ImageIO;
+
+public class ImageTest {
+
+    public static void main(String[] args) throws FileNotFoundException, IOException {
+        BufferedImage jpg = ImageIO.read(new FileInputStream(args[0]));
+        ImageIO.write(jpg, "png", new FileOutputStream(args[1]));
+    }
+
+}
diff --git a/src/test/resources/steaks.jpg b/src/test/resources/steaks.jpg
new file mode 100644
index 0000000..3da9778
Binary files /dev/null and b/src/test/resources/steaks.jpg differ